.TH std::filesystem::space_info 3 "2024.06.10" "http://cppreference.com" "C++ Standard Libary"
.SH NAME
std::filesystem::space_info \- std::filesystem::space_info

.SH Synopsis
   Defined in header <filesystem>
   struct space_info {

       std::uintmax_t capacity;
       std::uintmax_t free;        \fI(since C++17)\fP
       std::uintmax_t available;

   };

   Represents the filesystem information as determined by filesystem::space.

.SH Member objects

   capacity  total size of the filesystem, in bytes
             \fI(public member object)\fP
   free      free space on the filesystem, in bytes
             \fI(public member object)\fP
             free space available to a non-privileged process (may be equal or less
   available than free)
             \fI(public member object)\fP

.SH Non-member functions

   operator== compares two space_infos
   (C++20)    \fI(function)\fP

operator==(std::filesystem::space_info)

   friend bool operator==( const space_info&, const space_info& ) =       \fI(since C++20)\fP
   default;

   Checks if capacity, free and available of both arguments are equal respectively.

   This function is not visible to ordinary unqualified or qualified lookup, and can
   only be found by argument-dependent lookup when std::filesystem::space_info is an
   associated class of the arguments.

   The != operator is synthesized from operator==.

.SH Example


// Run this code

 #include <cstdint>
 #include <filesystem>
 #include <iostream>

 std::uintmax_t disk_usage_percent(const std::filesystem::space_info& si,
                                   bool is_privileged = false) noexcept
 {
     if (constexpr std::uintmax_t X(-1);
         si.capacity == 0 || si.free == 0 || si.available == 0 ||
         si.capacity == X || si.free == X || si.available == X
     )
         return 100;

     std::uintmax_t unused_space = si.free, capacity = si.capacity;
     if (!is_privileged)
     {
         const std::uintmax_t privileged_only_space = si.free - si.available;
         unused_space -= privileged_only_space;
         capacity -= privileged_only_space;
     }
     const std::uintmax_t used_space{capacity - unused_space};
     return 100 * used_space / capacity;
 }

 void print_disk_space_info(auto const& dirs, int width = 14)
 {
     (std::cout << std::left).imbue(std::locale("en_US.UTF-8"));

     for (const auto s : {"Capacity", "Free", "Available", "Use%", "Dir"})
         std::cout << "│ " << std::setw(width) << s << ' ';

     for (std::cout << '\\n'; auto const& dir : dirs)
     {
         std::error_code ec;
         const std::filesystem::space_info si = std::filesystem::space(dir, ec);
         for (auto x : {si.capacity, si.free, si.available, disk_usage_percent(si)})
             std::cout << "│ " << std::setw(width) << static_cast<std::intmax_t>(x) << ' ';
         std::cout << "│ " << dir << '\\n';
     }
 }

 int main()
 {
     const auto dirs = {"/dev/null", "/tmp", "/home", "/proc", "/null"};
     print_disk_space_info(dirs);
 }

.SH Possible output:

 │ Capacity       │ Free           │ Available      │ Use%           │ Dir
 │ 84,417,331,200 │ 42,732,986,368 │ 40,156,028,928 │ 50             │ /dev/null
 │ 84,417,331,200 │ 42,732,986,368 │ 40,156,028,928 │ 50             │ /tmp
 │ -1             │ -1             │ -1             │ 100            │ /home
 │ 0              │ 0              │ 0              │ 100            │ /proc
 │ -1             │ -1             │ -1             │ 100            │ /null

.SH See also

   space   determines available free space on the file system
   \fI(C++17)\fP \fI(function)\fP
